From 20749860ada1b0e8b3b00be8683d4e61530b2ae3 Mon Sep 17 00:00:00 2001
From: Danil Nikolaev <lischenkodev@gmail.com>
Date: Sun, 18 Jan 2026 16:28:53 +0300
Subject: [PATCH] add transliteration command (en <-> ru)

---
 src/commands/transliteration.ts | 113 ++++++++++++++++++++++++++++++++
 src/index.ts                    |   2 +
 src/util/utils.ts               |   6 ++
 3 files changed, 121 insertions(+)
 create mode 100644 src/commands/transliteration.ts

diff --git a/src/commands/transliteration.ts b/src/commands/transliteration.ts
new file mode 100644
index 0000000..c4e937c
--- /dev/null
+++ b/src/commands/transliteration.ts
@@ -0,0 +1,113 @@
+import {ChatCommand} from "../base/chat-command";
+import {Message} from "typescript-telegram-bot-api";
+import {logError, replyToMessage} from "../util/utils";
+
+const EN =
+    "`qwertyuiop[]asdfghjkl;'zxcvbnm,./" +
+    "~QWERTYUIOP{}ASDFGHJKL:\"ZXCVBNM<>?" +
+    "1234567890-=" +
+    "!@#$%^&*()_+";
+
+const RU =
+    "ёйцукенгшщзхъфывапролджэячсмитьбю." +
+    "ЁЙЦУКЕНГШЩЗХЪФЫВАПРОЛДЖЭЯЧСМИТЬБЮ," +
+    "1234567890-=" +
+    "!\"№;%:?*()_+";
+
+function makeMap(from: string, to: string): Map<string, string> {
+    if (from.length !== to.length) {
+        throw new Error(`Layout maps must be same length: ${from.length} vs ${to.length}`);
+    }
+    const m = new Map<string, string>();
+    for (let i = 0; i < from.length; i++) m.set(from[i], to[i]);
+    return m;
+}
+
+const enToRu = makeMap(EN, RU);
+const ruToEn = makeMap(RU, EN);
+
+function swapLayout(text: string, map: Map<string, string>): string {
+    let out = "";
+    for (const ch of text) out += map.get(ch) ?? ch;
+    return out;
+}
+
+export const toRuLayout = (text: string) => swapLayout(text, enToRu);
+export const toEnLayout = (text: string) => swapLayout(text, ruToEn);
+
+const reCyr = /\p{Script=Cyrillic}/u;
+const reLat = /\p{Script=Latin}/u;
+
+export type ScriptGuess = "ru" | "en" | "mixed" | "unknown";
+
+export function detectScript(text: string): ScriptGuess {
+    let cyr = 0, lat = 0;
+
+    for (const ch of text) {
+        if (reCyr.test(ch)) cyr++;
+        else if (reLat.test(ch)) lat++;
+    }
+
+    if (cyr === 0 && lat === 0) return "unknown";
+    if (cyr > 0 && lat > 0) return "mixed";
+    return cyr > 0 ? "ru" : "en";
+}
+
+const EN_VOWELS = /[aeiouy]/i;
+const RU_VOWELS = /[аеёиоуыэюя]/i;
+
+function vowelRatio(text: string, reLetter: RegExp, reVowel: RegExp): number {
+    let letters = 0, vowels = 0;
+    for (const ch of text) {
+        if (reLetter.test(ch)) {
+            letters++;
+            if (reVowel.test(ch)) vowels++;
+        }
+    }
+    return letters === 0 ? 0 : vowels / letters;
+}
+
+function looksLikeEnglish(text: string): boolean {
+    const ratio = vowelRatio(text, /\p{Script=Latin}/u, EN_VOWELS);
+    return ratio >= 0.20;
+}
+
+function looksLikeRussian(text: string): boolean {
+    const ratio = vowelRatio(text, /\p{Script=Cyrillic}/u, RU_VOWELS);
+    return ratio >= 0.18;
+}
+
+export function fixLayoutAuto(
+    text: string,
+    toRuLayout: (s: string) => string,
+    toEnLayout: (s: string) => string,
+): string {
+    const guess = detectScript(text);
+
+    if (guess === "en") {
+        if (looksLikeEnglish(text)) return text;
+        return toRuLayout(text);
+    }
+
+    if (guess === "ru") {
+        if (looksLikeRussian(text)) return text;
+        return toEnLayout(text);
+    }
+
+    return text;
+}
+
+export class Transliteration extends ChatCommand {
+    regexp = /^\/tr\s([^]+)/i;
+
+    async execute(msg: Message, match?: RegExpExecArray): Promise<void> {
+        const text = (match ? match[1] : "").trim();
+        if (text.length === 0) {
+            return;
+        }
+
+        const newText = fixLayoutAuto(text, toRuLayout, toEnLayout);
+
+        await replyToMessage(msg, newText).catch(logError);
+    }
+}
\ No newline at end of file
diff --git a/src/index.ts b/src/index.ts
index c6863c1..531479a 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -56,6 +56,7 @@ import {OllamaRequest} from "./model/ollama-request";
 import {CallbackCommand} from "./base/callback-command";
 import {OllamaCancel} from "./callback_commands/ollama-cancel";
 import {MistralChat} from "./commands/mistral-chat";
+import {Transliteration} from "./commands/transliteration";
 
 process.setUncaughtExceptionCaptureCallback(console.error);
 
@@ -133,6 +134,7 @@ export const chatCommands: ChatCommand[] = [
     new Distort(),
     new Dice(),
     new Title(),
+    new Transliteration(),
 
     new AdminsAdd(),
     new AdminsRemove(),
diff --git a/src/util/utils.ts b/src/util/utils.ts
index 90b2557..0a927fe 100644
--- a/src/util/utils.ts
+++ b/src/util/utils.ts
@@ -798,4 +798,10 @@ export async function imageToBase64(filePath: string): Promise<string> {
             resolve(dataUrl);
         });
     });
+}
+
+export function ifTrue(exp?: never): boolean {
+    if (!exp) return false;
+
+    return ["true", "t", "y", 1, "1"].includes(exp);
 }
\ No newline at end of file